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CoolROD · 08-05-2003, 06:30 PM

My Johnson C030P5-1 will lift a water column 83.1/2 inches --> My Eheim 1048 will lift water 61 inches. The numbers posted here indicate maximum lift above the the water level in which the pumps were submerged. The pumps were submerged about 2.1/2" at their inlet and oriented with their outlet at the top.

The Johnson will lift water well above 83.1/2 but the flow can not be maintained for any reasonable period of time. The numbers that I posted are the level at which the water receeds to and appears to stabilize. NOTE: The water level was not completely stable -It would oscillate up and down some fraction of an inch as the water column lifted and fell with some momentum. I was using 1/2" I/D hose.

The Johnson flow was very energetic compared to the Eheim 1048 and I feel that the 1/2" hose is a restriction because the pump gains efficiency with increased flow.

My king flow meter registered 1 GPM for the Eheim and 1.5 GPM for the Johnson. These numbers do not indicate the performance of the pump as the water coming out of the flow meter was only a small percentage of the pumps nonrestricted flow. My flow meter routes water through (4) 1/8" holes -very restrictive! I will time a measured volume through the pump(s) to try and gather enough points to generate a curve. Again, I think that I need to wait until I have some 3/4 I.D. hose to do the Johnson any justice.

Does anyone have any flow numbers for the Johnson to compare / contrast with mine?

08-05-2003, 06:30 PM	#214
CoolROD Cooling Savant Join Date: Mar 2003 Location: North Carolina, USA Posts: 225	My Johnson C030P5-1 will lift a water column 83.1/2 inches --> My Eheim 1048 will lift water 61 inches. The numbers posted here indicate maximum lift above the the water level in which the pumps were submerged. The pumps were submerged about 2.1/2" at their inlet and oriented with their outlet at the top. The Johnson will lift water well above 83.1/2 but the flow can not be maintained for any reasonable period of time. The numbers that I posted are the level at which the water receeds to and appears to stabilize. NOTE: The water level was not completely stable -It would oscillate up and down some fraction of an inch as the water column lifted and fell with some momentum. I was using 1/2" I/D hose. The Johnson flow was very energetic compared to the Eheim 1048 and I feel that the 1/2" hose is a restriction because the pump gains efficiency with increased flow. My king flow meter registered 1 GPM for the Eheim and 1.5 GPM for the Johnson. These numbers do not indicate the performance of the pump as the water coming out of the flow meter was only a small percentage of the pumps nonrestricted flow. My flow meter routes water through (4) 1/8" holes -very restrictive! I will time a measured volume through the pump(s) to try and gather enough points to generate a curve. Again, I think that I need to wait until I have some 3/4 I.D. hose to do the Johnson any justice. Does anyone have any flow numbers for the Johnson to compare / contrast with mine? __________________ Jack of all Trades, Master of None. Last edited by CoolROD; 08-07-2003 at 11:09 PM.